The clinical syndrome of psychopathic personality offers an important model for studying the interplay between emotion and attention. Psychopathy is theorized to involve a disconnection between cognitive representations and affective response, and empirical studies have revealed abnormalities in fear reactivity and in attentional processing in psychopathic individuals. Recent research with male prisoners using a picture-viewing paradigm suggests that: (a) psychopaths have a higher than normal threshold for the transition from stimulus orienting to defense, such that (in relation to nonpsychopaths) an aversive foreground must be more intense to produce defensive activation and startle reflex potentiation, and (b) psychopaths show an absence of startle response differentiation between affective and neutral foregrounds early (i.e., 300 ms) after picture onset, suggesting a deficiency in motivated attention (Lang, Bradley, and Cuthbert, 1997). Drawing on recent developments in the use of startle and brain-ERP measures to index affect and attention during picture processing, a series of three experiments is proposed to directly test the hypothesis that psychopathy involves a heightened aversion threshold, and to examine the mediating role of attention in this affective deviation. To examine the generality of the phenomena under study participants will include female as well as male prisoners, and also nonprisoner men with personality traits of psychopathy. Study I compares the startle-probe reactions during aversive pictures of varying intensity in psychopathic and nonpsychopathic women offenders. Study II compares emotional activation and attention- allocation to pleasant and unpleasant pictures of varying intensity in college men either high or low in features of psychopathy, using startle and ERP measures. Study III examines brain and blink indices of early attentional processing of affective and neutral pictures in psychopathic, nonpsychopathic, and antisocial prisoner men. This research should contribute to our understanding of pathological processes underlying psychopathy, and also to a basic understanding of emotion- attention interactions and normal variations in personality and behavior.